Hazard likelihood is the estimated probability that a particular hazard will occur, be present or cause exposure within a defined food-handling process. In a food-safety risk assessment, likelihood is considered alongside the potential severity of harm to help determine which hazards need the strongest controls.
A risk assessment may use qualitative categories such as rare, unlikely, possible, likely and almost certain, or a numerical scale defined by the organisation. The rating should be based on evidence and the specific process being assessed. Avoid assigning a likelihood simply because a food is commonly associated with a hazard; consider the actual product, supplier, controls and conditions.
Likelihood estimates how probable the hazard is. Severity estimates how serious the consequences could be if the hazard causes harm. Together they help determine risk and prioritise controls. A low-likelihood event may still require strong controls if its consequences could be severe.
Example: A restaurant assesses the likelihood of raw poultry contaminating ready-to-eat salad. The team reviews preparation layout, shared equipment, staff movement and cleaning procedures, then strengthens separation and verification where needed.
Chef’s tip: Reassess likelihood when suppliers, recipes, equipment, staff practices or production volumes change. A risk rating should reflect current conditions, not remain fixed indefinitely.
Key distinction: Hazard likelihood is the probability that a hazard will occur or cause exposure. Hazard severity describes the seriousness of the potential harm; risk assessment considers both.
This term is one of hundreds covered in depth across OCS courses, learning paths, and 1-on-1 coaching with Chef Eric.
